METHYLDIBROMOGLUTARONITRILE (EUXYL-K-400) - AN IMPORTANT NEW ALLERGENIN COSMETICS

Euxyl K 400 is a preservative system for cosmetics and toiletries that contains phenoxyethanol and methyldibromoglutaronitrile in a 4:1 rati o. In The Netherlands, Italy, and Germany, the prevalence of allergy t o Euxyl K 400 has risen in the past 4 years and is currently 2% to 4% in patients suspected of having contact dermatitis. The allergenic ing redient is nearly always methyldibromoglutaronitrile. Causative produc ts include both stay-on and rinse-off cosmetics and moistened toilet t issue. Because the causative products usually give false-negative reac tions, the allergen, methyldibromoglutaronitrile, should be tested in all patients suspected of having cosmetic dermatitis and in those with perianal dermatitis. We suggest a test concentration of 0.3% to 0.5% in petrolatum.